New Breakthroughs in China’s Coal Gasification Technology

It is learned from the 2013 Summit Forum on Strategic Development of Coal-to-Natural Gas in China that the China Sedin Engineering Company, Ltd. has developed with independent intellectual property rights two experimental furnaces for pressurized gasification of crushed coal, 5 m in inside diameter, while the whole design work was completed and the gasifiers have passed all preliminary tests to lay a solid foundation for the future commercial demonstration tests on gasification of crushed coal in the 5-meter-diameter pressure gasifiers. It is told that these two experimental gasifiers will serve as the backup gasifiers to be used in the second phase coal-to-natural gas project at the Xinjiang Qinghua Company.

According to the design the two novel pressure gasifiers are aimed at treating crushed coal with discharge of dry ash, with the inside diameter increased to 5 m from 3.8 m and the gasification pressure increased from 4.0 MPa to 5.0 MPa or 6.0 MPa. The gas output from a single gasifier can reach 130 thousand Nm3/h and its coal treating capacity is increased from 800 tons to 1 600 tons, with the gas output being nearly tantamount to that of a single fluidized bed gasifier. In the meantime, this kind of pressure gasifier features the matured technology and simplicity in operation, with its fabrication cost equating to one fourth or one third of the cost of other gasifiers.

According to the state policy on development of coal chemical industry, the minimum scale for coal-based natural gas production should reach at least 2.0 billion m3/a. If this size of gas output is to be provided by the crushed coal 5-m-diameter gasifier operating at the same pressure, the total amount of gasifiers will be reduced by 37%. In parallel with the commissioning of the first phase of project for manufacture of 4.0 billion m3/a of coal-based natural gas, the project has verified the viability of the pressure gasifier for treating crushed coal at 4.0 MPa, which has also proved the future possibility for adoption of the Cedin Company’s 5-m-diameter pressure gasifier for treating the crushed coal at a pressure of 4.0 MPa, which can be further increased to 5.0—6.0 MPa in practice.

This 5-m-diameter pressure gasifier for treating crushed coal with dry ash discharge has been fully endorsed by experts during their technical assessment. The management of the Datang International Company has consented on the capability of this kind of gasifier designed by the Sedin Engineering Company as saying: “Although the gasifier type for the phase II and phase III projects has been determined, we do not exclude the possibility of adopting Sedin’s 5-mdiameter gasifiers in other projects.”